How to replace occurrences of "-" with an empty string?

Question

I have this string: "123-456-7"

I need to get this string: "1234567"

How I can replace occurrences of "-" with an empty string?

score 105 · Accepted Answer · answered May 21 '09 at 20:15

105

string r = "123-456-7";
r = r.Replace("-", "");

answered May 21 '09 at 20:15

Sean Bright

118,630
17
138
146

5

Be careful, it won't work if you use single quotes (indicating a char) => `r.Replace('-', '');` That just bit me in the A** – Kellen Stuart May 15 '19 at 23:33

score 25 · Answer 2 · answered May 21 '09 at 20:16

25

This should do the trick:

String st = "123-456-7".Replace("-","");

answered May 21 '09 at 20:16

Jose Basilio

50,714
13
121
117

score 23 · Answer 3 · edited May 23 '17 at 12:32

23

string r = "123-456-7".Replace("-", String.Empty);

For .Net 1.0 String.Empty will not take additional space on the heap but "" requires storage on the heap and its address on the stack resulting in more assembly code. Hence String.Empty is faster than "".

Also String.Empty mean no typo errors.

Check the What is the difference between String.Empty and “” link.

edited May 23 '17 at 12:32

Community

1
1

answered May 22 '09 at 05:06

Rashmi Pandit

23,230
17
71
111

1

I do not believe this is true. String.Empty is the constant for "". The compiler points all "" literals to String.Empty. Doesn't matter how many "" literals you have. – AMissico Sep 02 '09 at 06:24
1

Thanks AMissico ... I just checked the heap for 3.5 framework and you are right, both "" and String.Empty point to the same location. But, for 1.0, there will be space allocated on the heap for "". I've edited the answer accordingly :) – Rashmi Pandit Oct 01 '10 at 03:58

score 4 · Answer 4 · answered May 21 '09 at 20:21

4

To be clear, you want to replace each hyphen (-) with blank/nothing. If you replaced it with backspace, it would erase the character before it!

That would lead to: 123-456-7 ==> 12457

Sean Bright has the right answer.

answered May 21 '09 at 20:21

abelenky

63,815
23
109
159

Syed Tayyab Ali · Answer 5 · 2011-05-02T19:12:55.787

2

String.Replace Method (String, String)

in your case it would be

string str = "123-456-7";
string tempstr = str.Replace("-","");

edited May 02 '11 at 19:12

answered May 21 '09 at 20:23

Syed Tayyab Ali

3,643
7
31
36

score -1 · Answer 6 · answered Dec 13 '12 at 23:30

-1

Use String.Empty or null instead of "" since "" will create an object in the memory for each occurrences while others will reuse the same object.

answered Dec 13 '12 at 23:30

Darshana

564
1
4
13

6

Just not true, see http://stackoverflow.com/questions/263191/in-c-should-i-use-string-empty-or-string-empty-or – weston Dec 13 '12 at 23:40
Correct! Sorry. I did had a wrong picture. Thanks for correcting me. – Darshana Dec 13 '12 at 23:55

How to replace occurrences of "-" with an empty string?

6 Answers6

Linked